1210115261 has 4 divisors (see below), whose sum is σ = 1262728992. Its totient is φ = 1157501532.

The previous prime is 1210115237. The next prime is 1210115273. The reversal of 1210115261 is 1625110121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1210115261 - 2⁶ = 1210115197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210115201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26306831 + ... + 26306876.

It is an arithmetic number, because the mean of its divisors is an integer number (315682248).

Almost surely, 2^1210115261 is an apocalyptic number.

It is an amenable number.

1210115261 is a deficient number, since it is larger than the sum of its proper divisors (52613731).

1210115261 is an equidigital number, since it uses as much as digits as its factorization.

1210115261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52613730.

The product of its (nonzero) digits is 120, while the sum is 20.

The square root of 1210115261 is about 34786.7109827877. The cubic root of 1210115261 is about 1065.6360710585.

Adding to 1210115261 its reverse (1625110121), we get a palindrome (2835225382).

The spelling of 1210115261 in words is "one billion, two hundred ten million, one hundred fifteen thousand, two hundred sixty-one".